Competition BBQ is a different beast, and cooks go to extremes to make the most out of one bite. I'm a BBQ Judge and I use some of he comp tips and tricks at home, but usually to a lesser degree. Injections are a good example, I use competition products, but my mixing ratio might be 1/3 of the amount used in competition.
To comment on the squeeze butter question.... In addition to wrapping, a lot of comp cooks are using the spray version of Parkay or I Can't Believe It's Not Butter during the cook. Parkay doesn't break like butter can, has a higher smoke point, it helps melt the sugars in the rub and to some degree it keeps the sugars in the rub from darkening or burning and adds a level of moisture. Some cooks will use butter flavored popcorn oil.